DRM and audio files

Good morning folks,

I need to protect some original audio files that will be streamed to a Flutter app. I am looking for a way to do this, what's your suggestion ? Purchasing a 3rd party service (do you feedback for any of them ?) or implement/take advantage of the tools that AWS or GCP have to achieve such a gol ? (I am pretty expert of the GCP stack, integration won't be a problem).

Have you any experience with this ?

Thanks